1. Field of the Invention
This invention relates to a surface processing method for processing the surface of an insulating article by ion injection and to a printer head provided in a printer configured for ejecting ink droplets to an article for printing to effect printing. This invention also relates to a substrate for a recording medium for supporting a signal recording layer of a recording medium.
2. Description of Related Art
For improving a variety of physical and chemical characteristics of an article being processed, such as hardness, elasto-plasticity, electrical conductivity, lubricating properties, durability, moisture-proofness, corrosion proofness, wettability or gas transmittance, there has been known a technique of implanting ions into the surface.
For implanting ions into the surface of an article being processed, there is a so-called ion beam implanting method of directly illuminating an ion beam on the article. However, the ion beam implanting method suffers from the problem that, if an article being processed has a three-dimensional structure, it is difficult to implant ions uniformly on the article surface.
For enabling uniform ion implantation on the article surface even if the article has a three-dimensional structure, there is proposed a technique of generating a plasma containing the ions to be implanted to implant the ions contained in the plasma into the article being processed. This technique is referred to below as a plasma implantation method.
In implanting ions by the plasma implantation method into the article, the article is placed in a plasma containing the ions to be implanted and a negative pulse voltage such as is shown in FIG. 1 is applied to the article. On applying the negative voltage to the article, the ions contained in the plasma are pulled into the article so that the ions are implanted on the article surface.
In the plasma implanting method, if the plasma containing the ions to be implanted is generated uniformly around the article being processed, the ions can be uniformly implanted on the article surface even if the article has a three-dimensional structure.
However, the above-described plasma implantation method is used exclusively for a case wherein the article to be processed is formed of an electrically conductive material, such as metal. The reason is that, if the article being processed is an insulating material, and ion implantation is executed by the plasma implantation method, electrical charges are accumulated in the article being processed, thus setting up what is called a charge-up state. If charge-up of the article being processed occurs in the plasma implantation method, the ions contained in the plasma cease to be pulled effectively into the article being processed. The result is that, if the plasma implantation method is applied to the insulating material, the process time is prolonged to render it difficult to improve the productivity.